Improvement in tanning leather



UNITED 'STA'I'ES PATENT OFFICE.

GEORGE GOODWIN, OF COOKSHIRE, QUEBEC, CANADA.

IMPROVEMENT IN TANNING LEATHER.

Specification forming part of Letters Patent No. 199,054, dated January8, 1878; application filed I March 1877.

To all whom it may concern Be it known that I, GEORGE GoonwiN, ofOookshire,in the county of Compton, Province of Quebec, and Dominion ofCanada, have invented a new and useful Improvement in TanningVVater-Proof Leather, of which the fol lowing is a specification:

The object of this invention is to furnish an improved process fortanning water proof leather for boots, gloves, lace-leather, belts,harness, and various other uses.

The invention consists in the process of tanning hides by means ofsulphuric acid, alum, japonica, salt, and water or bark-liquor, ashereinafter set forth, and in the mixture of alum, japonica, salt, andwater or bark-liquor, in the proportions hereinafter set forth, for

- tanning hides.

In carrying my invention into practical effeet I first lime the hides inthe usual way, take off the hair, and then put the skins into a solutionof sulphuric acid, in the proportion of four ounces of acid to tengallons of water.

.The skins are left in the solution for fortyeight hours, with frequentstirring. The skins are next put into a mixture of alum, japonica, salt,and water, in the proportions of two pounds of alum, two poimds ofjaponica, three quarts of salt, and-ten gallons of water, and handledwell for one week. This is the application for lace-leathers.

For uppers and other heavy stock, the solution of alum, japonica, andsalt should be re-f newed every three days for two weeks, and

the hides should be left in the last liquor for one week at least.

Boot and glove leather is drenched after liming in the ordinary way, andthe acid is not used when the leather is required to be very soft.

When the leather is required to be firm, I use the acid after the hidecomes from the lime, as hereinbefore described, or when it comes fromthe drench.

The alum, japonica, and salt may be used together in a mixture, ashereinbefore described, or each ingredient may be used by itself in theproportion given each for a week; but the time for the acid should notbe increased beyond that given.

Old bark-liquor may be used instead of water to change the color of thestock.

fiaving thus described my invention, I claim as new and desire to secureby Letters Patent An improved process of tanning hides after the hairhas been removed, so as to make water-proof leather, that consists infirst soaking and agitating them forty-eight hours in a solution ofsulphuric acid, and then treating them with a tanning-liquor formed ofalum,

two poimds; japonica, two pounds; salt, three quarts; and water, tengallons, as set forth.

GEORGE GOODWIN.

Witnesses:

M. E. 000K, M. R. Bron.

